Objective: To investigate the effect of rabbit bone marrow mesenchymal stem cells (MSCs) as seed cells for the repair of tendon defect.
Methods: The MSCs were isolated, amplified and identified by detection of surface protein CD44 mRNA. A 3 cm long defect was made in the Achilles tendon of the rabbit. The rabbits were divided into experimental (E) and control (C) groups. The autologous MSCs were implanted into a collagen-polyglycolic acid (PGA) scaffold to form a tissue-engineered tendon, which was then transplanted to bridge the defect in the E group, while only collagen-PGA was transplanted to bridge the defect in the C group. The transplanted tendon was observed grossly and microscopically at 4, 8, 12 weeks after operation.
Results: The cultured MSCs exhibited positive staining of CD44 on 11 days after in vitro culture. A tendon-like tissue could be discerned at the operation site in the E group 4 weeks after operation. Tendon-like cells similar to normal tendon tissue, being axially arranged in collagen matching the mechanical direction, with uniform morphology could be seen in E group 12 weeks after operation. The newly regenerated tissue in C group adhered to the adjacent tissue and was smaller than that in E group. The collagen fibers in the regenerated tissue were loose with reticular and filiform structure, and the cells were arranged disorderly 12 weeks after the transplantation.
Conclusion: It is feasible to repair the tendon defect with autologous MSCs as seed cells.